groff

Format output for a PostScript printer, saving the output to a file

$ groff [path/to/input.roff] > [path/to/output.ps]

$ groff -man -T ascii [path/to/manpage.1] | less --RAW-CONTROL-CHARS

$ groff -man -T html [path/to/manpage.1] > [path/to/manpage.html]

$ groff [-t] [-p] -[me] -T [pdf] [path/to/input.me] > [path/to/output.pdf]

$ eval "$(grog -T utf8 [path/to/input.me])"

groff [-abeghijklmnoqsStUvzCEGNRSXYZ] [-Aarg] [-darg] [-Darg] [-ffam] [-Fdir] [-Idir] [-Karg] [-Larg] [-Mdir] [-Parg] [-rarg] [-Targ] [-warg] [-Warg] [files…]

-Targ
    output device, e.g., ascii, utf8, ps, pdf, html

-mandoc
    use mandoc macro package for BSD man pages

-man
    use man macro package for Unix man pages

-mdoc
    use mdoc macro package

-me
    use me macro package

-mm
    use mm macro package

-mom
    use mom macro package

-ms
    use ms macro package

-Parg
    pass arg to PostScript prologue

-rreg=val
    set register reg to val

-Fdir
    font directory

-Mdir
    macro directory

-Idir
    include directory for soelim

-wname
    enable warning category name

-k
    use pre-grohtml (deprecated)

-l
    send output to spooler

-s
    stop after troff

-z
    suppress formatted output

-Z
    enable device-independent output

groff is the GNU implementation of the classic Unix roff typesetting system, serving as a modern replacement for troff and nroff. It formats input files written in the roff markup language, which uses macros, requests, and escape sequences to produce formatted output for various devices like terminals, PostScript, PDF, and HTML.

Primarily used for rendering Unix manual pages (man pages), groff also handles technical documentation, books, and reports. It supports preprocessors such as tbl for tables, eqn and pic for equations and diagrams, refer for bibliographies, and soelim for source file inclusion. The system is device-independent, allowing output tailored to specific formats via the -T option.

Invocation typically involves specifying a macro package (e.g., -man for man pages) and output device (e.g., -Tutf8 for terminals). Groff chains preprocessors automatically based on filename suffixes or explicit invocation. Its extensibility makes it powerful for precise typographic control, though the roff language has a steep learning curve.

Groff is integral to Unix-like systems, formatting most man pages via commands like man, which invokes groff -man -Tlocale file.1.

Roff syntax is arcane and error-prone; steep learning curve. Not suited for general document authoring—prefer Markdown or LaTeX. Some options device-specific; test output. Preprocessors must match input suffixes.

Automatically invoked: tbl (.tbl), eqn/. pic (.pic), chem (.chem). Use explicitly with groff -e -t -p etc.

Common: ascii, latin1, utf8, ps, dvi, pdf, X75, html, X*-* for X11.

-man (Unix), -mdoc (BSD), -ms (papers), -me (letters), -mm (memos), -mom (modern books).

Developed by James Clark starting 1990; first release 1.0 in 1991 as GNU troff. Merged with Berkeley tools; maintained by GNU since. Key enhancements: full Unicode, HTML/DVI/PDF output, better internationalization. Widely used for man pages since Linux adoption in 1990s.

nroff(1), troff(1), eqn(1), tbl(1), pic(1), refer(1), soelim(1), gtroff(1)